(a) Field of the Invention
The present invention relates to devices for display images, more particularly to, a device and method for driving a display device and a liquid crystal display apparatus employing the same.
(b) Description of the Related Art
Generally, a liquid crystal display (LCD) device includes two panels and a liquid crystal layer with dielectric anisotropy disposed between the two panels. The LCD device displays desired images by controlling an amount of light transmitting the two panels by means of strength of an electric field applied to the liquid crystal layer. The LCD device is one of flat panel display (FPD) devices. TFT-LCD devices having a thin film transistor in a pixel is widely used.
A TFT-LCD device generally includes pixels, gate lines, and data lines. The TFT-LCD device also includes a gate driver, a data driver, and a timing controller. The gate driver applies certain voltage to the gate lines for turning on the switching element, and the data driver applies data voltages to the data lines for displaying desired images.
The TFT-LCD device uses amorphous silicon or poly silicon as material thereof. Generally, it is easy for a poly silicon TFT-LCD to be integrated on a glass substrate because of high electron mobility. However, since an amorphous silicon (a-Si) TFT-LCD relatively has low electron mobility, it uses a separate driving IC mounting on the glass substrate.
In XGA product, this consists of 1024×3×768 pixels, and thus needs eight data driving ICs of 384 channels and three gate driving ICs of 256 channels or four data driving ICs of 384 channels and six gate driving ICs of 256 channels for driving the TFT-LCD device. Generally, the former is a single bank driving and the latter is a dual bank driving.
In the latter case, there are some problems in that a shift speed of shift registers is doubled in proportion to the number of the gate drivers. Also, there is a problem such that the gate driving ICs cannot be mounted on one side of the liquid crystal panel since the gate line pitch is three times as large as the date line pitch.